Starch content of SP tuber was determined by an enzymatic hydrolysis method using α-amylase and glucoamylase following AOAC method (18) with some modifications. SP tubers used in this research containedaround 24% starch. Since 50% of SP mash in distilledwater was applied, therefore the fermentation mediumcontained about 12% starch (120 g/L). From the results inTable